What he says about the circumferences of the wheels may seem superfluous, but he refers to the second clause of the verse, where he says, that these circumferences were full of eyes. Here, then, he now treats about their height and terrible aspect. It signifies that the wheels were large, for being round their length and breadth is equal. When he says they were lofty, he, doubtless, signifies that they inspire terror by their very appearance, as he afterwards expresses it.. The sum of the whole is, that these wheels were not common ones, but. they so exceeded the usual size that their magnitude was formidable. But all these things tend to impress the vision on the attention of the Prophet, because unless the Lord should, as it were, draw us violently to himself, we should become torpid through sloth. The Prophet then required to be so variously affected, that, as soon as he sees that no common vision is before him, he should apply all his faculties to its consideration. What he now says, that the circumferences of the wheels were full of eyes, signifies that all the wheels were not rashly but considerately put in motion. If the eyes had been in other parts, they had not been useful; but since the wheels turned by means of their felloes -- that is, their iron hoops -- there the Prophet saw the eyes fixed. Now, therefore, we see in what manner God directs the world in various ways, and yet nothing' is done without reason and plan. By the eyes, the Prophet understands, that providence which never wanders. He does not say, that every wheel had two eyes, but that the circumferences were full of eyes, which expresses much more than if he had said they possessed eyes: which means that there was not the least motion in the wheels unless arranged and governed with the utmost reason. And hence the error of those who think that years are intended by the entangled wheels is refuted. This idea they obtained, I suppose, front the Egyptians, for in their hieroglyphics the year is represented under the image of a serpent., which, being twisted round, bites his own tail. It is indeed true, that the continual series of time is so woven together that year draws year behind it, as Virgil also says in his second Georgic -- "The year returns into itself by its own footsteps." But this is altogether out of place here, where the Prophet; signifies that motions which seem to us confused are yet connected, because God does nothing either rashly or inconsiderately. Now, therefore, we comprehend the sense of this portion. He adds --

Rings - The felloes (circumference) of the wheels: they were both high and terrible. The "eyes" may have been no more than dazzling spots adding to their brilliancy. But it seems more likely that they had a symbolic meaning expressing either the universal fulfillment of God's will through His creation (2-Chronicles 16:9; compare Ezekiel 10:12), or the constant and unceasing praise which His works are ever rendering to Him Revelation 4:8. The power of nature is no blind force. it is employed in the service of God's Providence, and the stamp of reason is impressed all over it. It is this very thing that makes the power of nature terrible to him who is at enmity with God.

As for their rings - The strakes which form the rim or periphery.
They were dreadful - They were exceedingly great in their diameter, so that it was tremendous to look from the part that touched the ground to that which was opposite above.
Were full of eyes - Does not this refer to the appearance of nails keeping on the spokes, or strakes or bands upon the rim?

As for their rings, they were so high, that they were dreadful,.... The circles and circumferences of them were "high": which may denote the visibility and extensiveness of the churches of Christ, especially in the latter day; when they shall be exalted above the mountains and hills, the kingdoms and states of this world; and there shall be such numerous additions to them, that the place will be too strait for the members of them to dwell in, Isaiah 2:2; and "they were dreadful"; terrible, as the churches of Christ will be to their enemies to look at, when they shall be in their exalted state, Revelation 11:12; or the words may be rendered, "and they had fear" (s); there was fear and reverence in them; the fear of God, and a reverential affection for him; they were waiting on him, and attending his worship with great reverence and godly fear:
and their rings were full of eyes round about them four; everyone of the four wheels, and each of their four semicircles, were full of eyes; expressive of the knowledge of the Gospel, and the truths of it, in church members; their continual looking to Christ for fresh supplies of grace and strength; and their constant watchfulness over each other.
(s) "et timor illis erat", Cocceius; "et timor ipis", Starckius; "and they were reverent", so Dr. Lightfoot, Prospect of the Temple, &c. c. 38. p. 2055.

rings--that is, felloes or circumferences of the wheels.
eyes--The multiplicity of eyes here in the wheels, and Ezekiel 10:12, in the cherubim themselves, symbolizes the plenitude of intelligent life, the eye being the window through which "the spirit of the living creatures" in the wheels (Ezekiel 1:20) looks forth (compare Zac 4:10). As the wheels signify the providence of God, so the eyes imply that He sees all the circumstances of each case, and does nothing by blind impulse.

The rings - The circumference of the wheels. Dreadful - Their very height imprest a fear on the beholder. Them four - Every one of the four wheels. How fitly do the wheels, their motion, their height, and eyes, signify the height, unsearchableness, wisdom, and vigilance of the Divine Providence.